Interpenetrating network hydrogels with independently tunable stiffness

Abstract

Interpenetrating network hydrogels with independently tunable stiffness enhance tissue regeneration and wound healing.

1 . A 3-dimensional hydrogel comprising an interpenetrating network of alginate and collagen, wherein the hydrogel comprises a storage modulus of 30 Pa or greater. 
     
     
         2 . The hydrogel of  claim 1 , wherein the hydrogel comprises a storage modulus of 400 Pa or less. 
     
     
         3 . The hydrogel of  claim 1 , wherein the alginate lacks a cell adhesion molecule. 
     
     
         4 . The hydrogel of  claim 3 , wherein the cell adhesion molecule comprises a polypeptide comprising the amino acid sequence, arginine-glycine-aspartate (RGD). 
     
     
         5 . The hydrogel of  claim 1 , wherein the hydrogel does not comprise any covalent crosslinks. 
     
     
         6 . The hydrogel of  claim 1 , wherein the alginate is crosslinked to form a mesh structure. 
     
     
         7 . The hydrogel of  claim 6 , wherein the alginate is ionically crosslinked. 
     
     
         8 . The hydrogel of  claim 7 , wherein the alginate is ionically crosslinked by divalent or trivalent cations. 
     
     
         9 . The hydrogel of  claim 8 , wherein the divalent cation comprises Ca 2+ . 
     
     
         10 . The hydrogel of  claim 1 , wherein the alginate comprises a molecular weight of at least 100 kDa. 
     
     
         11 . The hydrogel of  claim 1 , wherein the hydrogel comprises a dextran diffusion coefficient of 2.5×10 −7  to 1×10 −6  cm 2 /s. 
     
     
         12 . The hydrogel of  claim 1 , wherein the hydrogel comprises multidirectional collagen fibrils. 
     
     
         13 . The hydrogel of  claim 1 , wherein the hydrogel comprises a collagen concentration of about 1.5 mg/mL. 
     
     
         14 . The hydrogel of  claim 1 , wherein the hydrogel comprises an alginate concentration of about 5 mg/mL. 
     
     
         15 . The hydrogel of  claim 1 , wherein the hydrogel comprises interconnected pores. 
     
     
         16 . The hydrogel of  claim 15 , wherein the interconnected pores comprise nanopores. 
     
     
         17 . The hydrogel of  claim 1 , wherein the hydrogel comprises a relative concentration of carbon of 10-50% weight/weight; or a relative concentration of oxygen of 50-70% weight/weight; or a relative concentration of potassium of 0.5-2% weight/weight; or a relative concentration of calcium of 0.5-10% weight/weight. 
     
     
         18 - 20 . (canceled) 
     
     
         21 . The hydrogel of  claim 1 , further comprising a mammalian cell. 
     
     
         22 . The hydrogel of  claim 21 , wherein the mammalian cell comprises a fibroblast. 
     
     
         23 . The hydrogel of  claim 22 , wherein the fibroblast comprises a dermal fibroblast or a healthy fibroblast. 
     
     
         24 . (canceled) 
     
     
         25 . The hydrogel of  claim 21 , wherein the cell is in/on the hydrogel and comprises a spindle-like cell shape. 
     
     
         26 . The hydrogel of  claim 21 , wherein the cell is in/on the hydrogel and comprises a stress fiber. 
     
     
         27 . A wound dressing material comprising the hydrogel of  claim 1 . 
     
     
         28 . The wound dressing material of  claim 27 , further comprising an anti-microbial or anti-inflammatory agent. 
     
     
         29 . A method of promoting tissue repair, tissue regeneration, or wound healing comprising administering the hydrogel of  claim 1  to a subject in need thereof. 
     
     
         30 . The method of  claim 29 , wherein the subject comprises an injured tissue. 
     
     
         31 . The method of  claim 30 , wherein the subject comprises a chronic, non-healing wound, an ischemic wound, an infected wound or a wound caused by continued trauma. 
     
     
         32 . The method of  claim 31 , wherein the subject comprises a diabetic wound or ulcer. 
     
     
         33 . (canceled) 
     
     
         34 . The method of  claim 29 , wherein the hydrogel is seeded with mammalian cells prior to administration. 
     
     
         35 . The method of  claim 34 , wherein the hydrogel is encapsulated with mammalian cells prior to administration. 
     
     
         36 . The method of  claim 29 , wherein the hydrogel contacts a mammalian cell after administration. 
     
     
         37 . The method of  claim 29 , wherein the hydrogel downregulates the expression of an inflammation associated protein, a cell adhesion or extracellular matrix protein, a collagen protein, HGF or WNT5A. 
     
     
         38 - 40 . (canceled) 
     
     
         41 . The method of  claim 37 , wherein the inflammation associated protein comprises interleukin-10 (IL-10) and/or COX-2. 
     
     
         42 . The method of  claim 29 , wherein the hydrogel upregulates the expression of an inflammation associated protein.